WALTHAM — The NBA announced Monday night that in light of the tragic events at the Boston Marathon Monday afternoon, Tuesday night’s scheduled Celtics game with the Indiana Pacers at TD Garden has been canceled.

Since the season concludes Wednesday with both teams in action, there will be no makeup date and both teams will finish with 81 games played. The game was scheduled for 8 p.m. and was to be televised nationally by Turner Network Television.

It is uncertain when the Celtics will travel to Toronto for Wednesday’s season finale.

According to STATS, this the first time in NBA history that not every team has played the same number of games.

The first two games of the Celtics’ scheduled first-round playoff series with the Knicks are set for Madison Square Garden in New York, so it’s likely the Celtics won’t play at home until next weekend at the earliest.

The Bruins postponed their scheduled Monday night game with the Ottawa Senators. The Pacers had a practice scheduled at Emerson College Monday afternoon but the coaches canceled it Sunday night.

According to a Pacers official, the team was attempting to leave Boston late Monday night but was more likely to fly back to Indianapolis Tuesday. The Pacers (third) and Celtics (seventh) are both locked into their playoff seeds, making the league’s decision to cancel the game less complicated.

Knicks a topic

The topic prior to practice Monday morning was the Celtics’ playoff opponent, the Knicks, who beat Indiana Sunday to seal the second seed in the East. The Celtics are preparing for an emotional series against an archrival.

Kevin Garnett had nothing but positives to say about the Knicks. He was involved in a bizarre altercation with Carmelo Anthony near the team bus following the Celtics’ Jan. 7 win at MSG, during which there was trash talking. The two since have settled matters.

“Melo’s playing unbelievable; I think the whole team’s playing connected,” Garnett said. “They’re going to be a task at hand, obviously something to reckon with, we have our work cut out for us. I think the Knicks-Celtics matchup is just going to be what it is. It’s always been tradition because of the ties. Nothing less than that.”

The Knicks won the final three meetings of the season between the teams, including the last two by an average of 17 points. New York drained 22 3-pointers in those two victories. What’s more, the Knicks are fifth in the NBA in 3-point percentage and first in makes (10.9) and attempts (28.9). The Celtics average 17.2 attempts per game.

“We’ve definitely got to take the threes away, slow down the transition, they love to run,” Garnett said. “We’ve just got to be connected, know our game plans in our sleep, and come out and execute it.”

While coach Doc Rivers said he wanted to avoid the top-seeded Heat, he had no such trepidation about facing the Knicks. The Celtics swept New York in the playoffs in the first round two years ago as the third seed.

“I don’t want anyone, but it’s smart not to play the No. 1 team in the NBA in the first round, that’s not a slight on New York,” Rivers said. “I just use Marquette logic on that one. I don’t feel any different [as an underdog]. We don’t feel any different as underdogs. [The media] calls us underdogs. We were an underdog seed last year and throughout. For us, we just keep rolling.”

Pierce feels ill

The Celtics practiced without forward Paul Pierce, who did not come to the Sports Authority Training Center because of an illness. With no game Tuesday, it is not certain if Pierce and Garnett will play in the season finale at Toronto. Rivers said before the cancelation he had planned to play the duo in one of the final two games . . . Rivers said he would give Jason Terry
Wednesday night off if he asked because of sore legs . . . The Celtics are contemplating staying in Toronto Thursday, which would be an offday, and then flying to New York Friday to prepare a likely Game 1 Saturday. The NHL’s Rangers are scheduled to play a nationally televised 3 p.m. game Sunday against the New Jersey Devils, likely pushing the Knicks-Celtics opener to Saturday.